Systems and method for exhaust warm-up strategy

ABSTRACT

Methods and systems are provided for controlling a vehicle engine to adjust exhaust warm-up strategy based on a vehicle network information. In one example, in response to an expected decrease in temperature of a catalyst of a vehicle below a threshold and an estimated duration thereof based on communications external from the vehicle, a method may include delaying catalyst heating actions, when the catalyst heating actions are determined to be unable to heat up the catalyst to threshold temperatures. However, the catalyst heating actions may be enabled when the catalyst heating actions are determined to be able to achieve the threshold temperature within the duration.

FIELD

The present description relates generally to methods and systems forcontrolling a vehicle engine to adjust exhaust warm-up strategy based ona vehicle network information.

BACKGROUND/SUMMARY

Diesel and gasoline vehicle exhaust systems may include one or morecatalytic and/or emissions storage devices. As such, each device mayoperate at an optimal temperature (also known as the light-offtemperature) and various heating actions may be taken in the powertrainto deliver heat to the exhaust system in order to heat the device to itsoptimal operating temperature. The heating actions may include (but notlimited to) delaying combustion with injection or spark timing, changingexhaust gas recirculation (EGR) rate, delaying transmission shift point,and increasing engine load with accessory loads and the like.

Each of these aforementioned heating actions may negatively affectvehicle fuel economy and may have a noticeable impact on the driverexperience. Further, certain drive conditions (like extended idle, forexample) may not allow enough heat to get to the exhaust system tolight-off the active exhaust components even with the intrusivepowertrain actions mentioned above. During such driving conditions, anyaction taken to warm the exhaust is wasted because it may not yield thedesired emissions reduction implying that fuel economy is reduced andthe driver may be negatively impacted for no net benefit.

One example is shown by Bergeal et al. in WO 2011077125 A1, wherein adiesel engine includes a catalyst, and an engine management system thatdetects idle condition, and stops the engine entirely. The catalystdesign incorporates a honeycomb substrate and is further coated with acatalytic washcoat and is arranged such that it may be able balance thedemands of the low catalyst light-off temperature to treat cold-startemissions. However, the design of the catalyst is such that it may belimited to a particular engine system, diesel engines fitted withstart/stop technology, for example.

The inventors have recognized the above issues and identified aninteractive approach that may address the issue of drive conditionrelated catalyst heating actions across different types of vehiclesystems. In one example, the issues above may be address by a methodcomprising adjusting catalyst heating actions in response to an expecteddecrease in temperature of a catalyst of a vehicle below a threshold andan estimated duration thereof based on communications external from thevehicle, including delaying the actions based on the actions determinedto be unable to achieve the threshold within the duration, and enablingthe actions based on the actions determined to be able to achieve thethreshold within the duration. Thus, by anticipating drive conditionswherein the exhaust cannot be warmed to operating temperature, intrusiveexhaust warm-up actions may be delayed or in some cases inhibited, untila more favorable driving condition occurs.

As an example, a current and a future driving condition may bedetermined based on a communication within a vehicle-to-vehicle (V2V)network formed between vehicles within a threshold distance of a targetvehicle and further communication with a cloud. Additionally, a driverdestination information may be determined either from an in vehiclenavigation system or from the navigation system of a blue tooth device.Based on the driving condition, a target vehicle may be able to avail ofinformation from a lead network of vehicles to make intelligentdecisions related to whether or not to take intrusive actions tomaintain or increase exhaust temperature. In this way, an optimalstrategy may be devised that continuously monitors fuel cost of heatingand the impact to the driver versus delaying catalyst heating until morefavorable conditions exist.

It should be understood that the summary above is provided to introducein simplified form a selection of concepts that are further described inthe detailed description. It is not meant to identify key or essentialfeatures of the claimed subject matter, the scope of which is defineduniquely by the claims that follow the detailed description.Furthermore, the claimed subject matter is not limited toimplementations that solve any disadvantages noted above or in any partof this disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a schematic depiction of a vehicle system.

FIG. 2 schematically shows an engine system.

FIG. 3 shows an example embodiment of the vehicle system comprising anavigation system, in communication with an external network and a fleetof vehicles.

FIG. 4 shows a flow chart illustrating an example method for adjustingcatalytic heating actions based on the actions are determined to be ableto heat up the catalyst to threshold temperature.

FIG. 5 shows a flow chart illustrating an example method for adjustingcatalyst warm-up actions when a vehicle is in extended idle condition.

FIG. 6 shows a flow chart illustrating an example method for adjustingcatalyst heating based on destination input received from a driver ofthe hybrid electric vehicle and a predicted start/stop of the vehicle.

FIG. 7 shows an example relationship between vehicle speed and catalysttemperature.

FIG. 8 shows an example relationship between a state of charge in thehybrid electric vehicle and operating an engine of the hybrid vehiclebased on the catalyst temperature.

DETAILED DESCRIPTION

The following description relates to systems and methods for controllingexhaust catalyst heating actions. An example vehicle system including ahybrid drive is depicted in FIG. 1 and an example engine system is shownin FIG. 2. The present description may provide benefits for gasoline,diesel and alternative fuel engines as well. Accordingly, thisdisclosure is not limited to a particular type of engine or a particularexhaust system configuration. As such, the vehicle system may include anavigation system, which may be in communication with a network cloud, afleet of vehicles and with a controller of the vehicle system toascertain a present driving condition of the vehicle and further predicta future driving condition. Certain drive conditions may not allowenough heat to get the exhaust system to activate exhaust components.The controller may be configured to perform a control routine, such asthe routine of FIG. 4 to identify such drive conditions and furtherdelay exhaust warm up actions. In one example, if a vehicle speed fallsbelow threshold and continues to stay below threshold for a certainduration (extended idle condition, for example), the controller mayperform a routine such as the routine of FIG. 5 to delay the catalystheating actions. An example relationship between a vehicle speed andcatalyst temperatures is shown in FIG. 7. In another example, thecontroller may control exhaust warm-up based on a predicted number ofstart/stop in a route planned for a hybrid vehicle based on adestination input by a driver of the vehicle by performing the routineshown in FIG. 6. An example relationship between a state of charge inthe hybrid electric vehicle and operating an engine of the vehicle basedon the catalyst temperature is shown in FIG. 8. In this way, byanticipating drive conditions wherein the exhaust may not be warmed upto operating temperature, and delaying or stopping the intrusive exhaustwarm-up actions, driver experience may be enhanced and further cost ofheating may be reduced.

FIG. 1 illustrates an example vehicle propulsion system 100. Vehiclepropulsion system 100 includes a fuel burning engine 10 and a motor 120.As a non-limiting example, engine 10 comprises an internal combustionengine and motor 120 comprises an electric motor. Motor 120 may beconfigured to utilize or consume a different energy source than engine10. For example, engine 10 may consume a liquid fuel (e.g., gasoline) toproduce an engine output while motor 120 may consume electrical energyto produce a motor output. As such, a vehicle with propulsion system 100may be referred to as a hybrid electric vehicle (HEV).

Vehicle propulsion system 100 includes wheels 102. Torque is supplied towheels 102 via engine 10 and transmission 104. In some embodiments,motor 120 may also provide torque to wheels 102.

Vehicle propulsion system 100 may utilize a variety of differentoperational modes depending on operating conditions encountered by thevehicle propulsion system. Some of these modes may enable engine 10 tobe maintained in an off state where combustion of fuel at the engine isdiscontinued. For example, under select operating conditions, motor 120may propel the vehicle via transmission 104 as indicated by arrow 122while engine 10 is deactivated.

During other operating conditions, motor 120 may be operated to chargean energy storage device such as battery 108. For example, motor 120 mayreceive wheel torque from transmission 104 as indicated by arrow 122where the motor may convert the kinetic energy of the vehicle toelectrical energy for storage at battery 108. Thus, motor 120 canprovide a generator function in some embodiments. However, in otherembodiments, alternator 110 may instead receive wheel torque fromtransmission 104, or energy from engine 10, where the alternator 110 mayconvert the kinetic energy of the vehicle to electrical energy forstorage at battery 108.

During still other operating conditions, engine 10 may be operated bycombusting fuel received from a fuel system (not shown in FIG. 1). Forexample, engine 10 may be operated to propel the vehicle viatransmission 104 as indicated by arrow 112 while motor 120 isdeactivated. During other operating conditions, both engine 10 and motor120 may each be operated to propel the vehicle via transmission 104 asindicated by arrows 112 and 122, respectively. A configuration whereboth the engine and the motor may selectively propel the vehicle may bereferred to as a parallel type vehicle propulsion system. Note that insome embodiments, motor 120 may propel the vehicle via a first drivesystem and engine 10 may propel the vehicle via a second drive system.

Operation in the various modes described above may be controlled by acontroller 12. For example, controller 12 may identify and/or controlthe amount of electrical energy stored at the energy storage device,which may be referred to as the state of charge (SOC). Controller 12will be described below in more detail with respect to FIG. 2.

FIG. 2 shows a schematic depiction of additional components of vehiclepropulsion system 100. The vehicle system 100 includes an engine system8, a control system 14, and a fuel system 18. The engine system 8 mayinclude an engine 10 having a plurality of cylinders 30. The engine 10includes an engine intake 23 and an engine exhaust 25. The engine intake23 includes a throttle 62 fluidly coupled to the engine intake manifold44 via an intake passage 42.

The engine exhaust 25 includes an exhaust manifold 48 leading to anexhaust passage 35 that routes exhaust gas to the atmosphere. The engineexhaust 25 may include one or more emission control devices 70, whichmay be mounted in a close-coupled position in the exhaust. One or moreemission control devices may include a three-way catalyst, selectivecatalytic reduction (SCR) system, lean NOx trap, diesel particulatefilter (DPF), oxidation catalyst, etc. Emission control device 70 mayutilize reducants in the exhaust stream, such as urea or unburnt fuel,to reduce substrates such as NOx and CO in the exhaust. As such,emission control device 70 may include a reductant injector. In otherembodiments, reductants may be introduced via a fuel injection system inthe engine. It will be appreciated that other components may be includedin the engine such as a variety of valves and sensors.

Fuel system 18 may include a fuel tank 20 coupled to a fuel pump system21. The fuel pump system 21 may include one or more pumps forpressurizing fuel delivered to the injectors of engine 10, such as theexample injector 66 shown. While only a single injector 66 is shown,additional injectors are provided for each cylinder. It can beappreciated that fuel system 18 may be a return-less fuel system, areturn fuel system, or various other types of fuel system.

The fuel tank 20 may hold a plurality of fuel blends, including fuelwith a range of alcohol concentrations, such as various gasoline-ethanolblends, including E10, E85, gasoline, diesel, etc., and combinationsthereof.

The vehicle system 100 may further include control system 14. Controlsystem 14 is shown receiving information from a plurality of sensors 16(various examples of which are described herein) and sending controlsignals to a plurality of actuators 81 (various examples of which aredescribed herein). As one example, sensors 16 may include exhaust gassensor 126 and temperature sensor 127 located upstream of the emissioncontrol device, and airflow sensor, exhaust gas sensor 128, andtemperature sensor 129 located downstream of the emission controldevice. Other sensors such as pressure, temperature, air/fuel ratio, andcomposition sensors may be coupled to various locations in the vehiclesystem 100. Some more sensors include catalyst temperature sensors 125coupled to one or more catalysts coupled to the exhaust system. Asanother example, the actuators may include fuel injector 66 and throttle62. In addition, controller 12 may receive data from a navigation device34 (such as GPS) and/or a vehicle-to-vehicle (V2V) network such as anoff-board cloud network 13.

The control system 14 may include a controller 12 comprising a computerreadable storage medium comprising instructions that may be executed tocarry out one more control routines. The controller may receive inputdata from the various sensors, process the input data, and trigger theactuators in response to the processed input data based on instructionor code programmed therein corresponding to one or more routines.Example control routines are described herein with regard to FIGS. 4-6.

The efficiency of an exhaust-gas aftertreatment device is dependent uponthe operating temperature of the exhaust-gas aftertreatment device.Typically, in gasoline engines, catalytic reactors may use catalyticmaterials which increase the rate of certain reactions, ensuring anoxidation of HC and CO even at low temperatures. If nitrogen oxides(NOx) are additionally to be reduced, this may be achieved through theuse of a three-way catalytic converter. Herein, the nitrogen oxides NOxare reduced by means of the non-oxidized exhaust-gas components whichare present, specifically the carbon monoxides and the unburnedhydrocarbons, wherein said exhaust-gas components are oxidized at thesame time.

In combustion engines which are operated with an excess of air, that isto say for example engines which operate in the lean-burn mode, but inparticular direct-injection diesel engines or also direct-injectionengines, the nitrogen oxides contained in the exhaust gas cannot bereduced out of principle, that is to say on account of the lack ofreducing agent.

For the oxidation of the unburned hydrocarbons and of carbon monoxide,provision is made in particular of an oxidation catalytic converter inthe exhaust-gas flow. To realize an adequate conversion, a certainoperating temperature is demanded. The so-called light-off temperaturemay be 120° C. to 250° C.

To reduce the nitrogen oxides, use is also made of selective catalyticconverters, so-called SCR catalytic converters, in which reducing agentis purposely introduced into the exhaust gas in order to selectivelyreduce the nitrogen oxides. As reducing agent, in addition to ammoniaand urea, use may also be made of unburned hydrocarbons. The latter isalso referred to as HC enrichment, with the unburned hydrocarbons beingintroduced directly into the exhaust tract or else being supplied bymeans of engine-internal measures, specifically by means of apost-injection of additional fuel into the combustion chamber after theactual combustion.

It is basically also possible to reduce the nitrogen oxide emissions bymeans of so-called nitrogen oxide storage catalytic converters. Here,the nitrogen oxides are initially absorbed, that is to say collected andstored, in the catalytic converter during a lean-burn mode of thecombustion engine before being reduced during a regeneration phase forexample by means of substoichiometric operation (for example λ<0.95) ofthe combustion engine with a lack of oxygen.

Further possible engine-internal measures for realizing rich, that is tosay substoichiometric operation of the combustion engine are exhaust-gasrecirculation and, in the case of diesel engines, throttling in theintake tract. It is possible to dispense with engine-internal measuresif the reducing agent is introduced directly into the exhaust tract, forexample by means of an injection of additional fuel. During theregeneration phase, the nitrogen oxides are released and convertedsubstantially into nitrogen dioxide (N2), carbon dioxide (CO2) and water(H2O). The frequency of the regeneration phases is determined by theoverall emissions of nitrogen oxides and the storage capacity of thenitrogen oxide storage catalytic converter.

The temperature of the storage catalytic converter typically lies withina temperature window between 200° C. and 450° C., such that firstly afast reduction of the nitrogen oxides is ensured and secondly nodesorption without conversion of the re-released nitrogen oxides takesplace, such as may be triggered by excessively high temperatures.

One difficulty in the use of the storage catalytic converter in theexhaust track arises from the sulfur contained in the exhaust gas, whichsulfur is likewise absorbed in the storage catalytic converter and maybe regularly removed by means of a desulfurization. For this purpose,the storage catalytic converter may be heated to high temperatures,usually of between 600° C. and 700° C., and supplied with a reducingagent, which in turn can be attained by means of a transition to richoperation of the combustion engine. The higher the temperature of thestorage catalytic converter is, the more effective the desulfurizationis, wherein an admissible maximum temperature may not be exceeded,because then the desulfurization of the storage catalytic convertercontributes significantly to the thermal aging of the storage catalyticconverter as a result of excessively high temperatures. This adverselyaffects the desired conversion of the nitrogen oxides toward the end ofthe service life of the catalytic converter, wherein in particular thethermal storage capacity decreases as a result of thermal aging.

To minimize the emissions of soot particles, use is made of so-calledregenerative particle filters which filter the soot particles out of theexhaust gas and store them, with said soot particles being burned offintermittently during the course of the regeneration of the filter,usually at high temperatures of around 550° C. Here, the regenerationintervals are determined inter alia by the exhaust-gas back pressure,which is generated as a result of the increasing flow resistance of thefilter on account of the increasing particle mass in the filter.

Since both the exhaust gases of gasoline engines and also the exhaustgases of diesel engines contain unburned hydrocarbons (HC), carbonmonoxide (CO), nitrogen oxides (NOx) and also soot particles—albeit indifferent quantities and qualities—use is generally made of combinedexhaust-gas aftertreatment devices which comprise one or more of theabove-described catalytic converters and/or filters.

The increasing use of hybrid drives, in which conventionally in eachcase a combustion engine and an electric motor provide an output power,for example for driving a motor vehicle, offers completely newpossibilities for the control of exhaust-gas aftertreatment devices, inparticular with regard to optimum exhaust-gas purification or conversionperformance under different operating conditions.

For efficient control, it is advantageous for suitable measurementdevices, for example temperature sensors and/or flow sensors and/orsensors for determining chemical substances or elements contained in theexhaust-gas flow, to be provided in or near the exhaust-gas treatmentdevice, in particular upstream and/or downstream of the exhaust-gasaftertreatment device as viewed in the exhaust-gas flow direction. It isthereby possible to determine the temperature window suitable for therespective optimum operation of the exhaust-gas aftertreatment device,and if appropriate to adapt or change said temperature window to certainoperating states of the exhaust-gas aftertreatment device, for examplefor the regeneration of a soot particle filter and/or of a nitrogenoxide storage catalytic converter.

As described earlier, the diesel and gasoline engines include one ormore catalytic and/or emissions storage device. Each of these devicesmay function at high operating temperatures. To expedite the function ofthese devices various actions may be taken in the powertrain to deliverheat to the exhaust system including (but not limited to) delayingcombustion with injection or spark timing, changing exhaust gasrecirculation rate, delaying transmission shift point, and increasingengine load with accessory loads and the like. In case of hybridvehicles, a combustion engine of the hybrid vehicle may be turned ON tofacilitate catalyst warm-up, for example. However, each action maynegatively affect vehicle fuel economy and may further have a noticeableimpact on the driver experience.

Certain drive conditions, however, do not allow enough heat to get tothe exhaust system to light-off the active exhaust components even withthe intrusive powertrain actions mentioned above. During extended engineidle, for example, any action taken to warm the exhaust may be wasted asit may not yield the desired emissions reduction. Herein, fuel economymay be reduced and the driver may be negatively impacted for no netbenefit. The inventors have recognized that it may desirable toanticipate such drive conditions based on one or more of avehicle-to-vehicle (V2V) network, navigation data and drive history. Bypredicting the drive conditions in advance, exhaust warm-up actions maybe delayed when the exhaust cannot be warmed to operating temperature orenabled when exhaust may be able to reach the operating temperature.

Thus, a target vehicle may be able to obtain information from a leadnetwork of vehicles to make intelligent decisions related to whether ornot to take intrusive actions to maintain or increase exhausttemperature. FIG. 3 shows a vehicle in communication with a networkcloud and other vehicles in a fleet operating within a certain radius.In an embodiment 300 of a vehicle system 310, the vehicle system 310 maybe in communication with an external network (cloud) 360 and a fleet ofvehicles 320.

The vehicle system 310 may include a vehicle control system 312 that mayfurther include a controller 314. The control system 312 may be anexample of the control system 14 of FIG. 2. The controller 314 may be anexample of the controller 12 of FIGS. 1 and 2 and may further performone or more methods described herein in some embodiments. A navigationsystem 354 may be coupled to the control system 312 to determinelocation of the vehicle 310 at key-on and at any other instant of time.The navigation system 354 may be configured as a component of a motorvehicle navigation system, as a handheld device, as a component of asmart phone, and/or as any other suitable computing device(s). At avehicle key-off, the last location (e.g., GPS co-ordinates of thevehicle) of the vehicle 310 as estimated by the navigation system 354may be stored by the control system 312 for use during the next key-onevent. The navigation system may be connected to an external serverand/or network cloud or cloud-based server 360 via wirelesscommunication 350. The controller 314 may be able to run an applicationfor connecting to a cloud-based server 360 and/or collecting informationfor transmission to the cloud-based server 360. The application mayretrieve information gathered by vehicle systems/sensors, input devices,devices such as a mobile device connected via a Bluetooth link, and thelike. The navigation system 354 may determine the current location ofthe vehicle 310 and obtain ambient condition data (such as temperature,pressure etc.) from a network cloud 360. The network cloud 360 mayinclude real-time traffic condition road condition, vehicle speed oftarget vehicle, average vehicle speed of vehicles in the network, andthe like. The controller 312 may be coupled to a wireless communicationdevice 352 for direct communication of the vehicle 310 with a networkcloud 360. Using the wireless communication device 352, the vehicle 310may retrieve ambient condition data (such as temperature, pressure etc.)from the network cloud 360 to determine one or more of a current drivingcondition and a future driving condition.

Control system 312 is shown receiving information from a plurality ofsensors 316 and sending control signals to a plurality of actuators 318.As one example, sensors 316 may include manifold absolute pressureIntake air temperature (IAT) sensor, outside air temperature (OAT)sensor (MAP) sensor, barometric pressure (BP) sensor, exhaust gas oxygensensor (such as a UEGO sensor), fuel tank pressure sensor, canistertemperature sensor, catalyst temperature, vehicle speed and the like.Based on signals received from the different sensors 316, the engineoperations are regulated and consequently the controller 314 sendscontrol signals to engine actuators 318.

A fleet 320 of vehicles is shown in FIG. 3. A fleet 320 may comprise ofmultiple vehicles 322, 324, 326, and 328. In one example, vehicles322-328 may each be similar in make and model to the vehicle 310. Inalternate examples, vehicles 322-328 may be vehicles within a thresholddistance of vehicle 310. Further still, vehicles 322-328 may be vehiclesthat are part of a common fleet as vehicle 310. Each vehicle of thefleet 320 may comprise a control system 312 similar to the controlsystem 312 of vehicle 310. A navigation system 354 and a wirelesscommunication device 352 may be coupled to the control system 312 ofeach vehicle in the fleet 320. The on-board controllers in the vehiclesin the fleet may communicate with each other and to the on-boardcontroller in vehicle 310 via their respective navigation system 354,via wireless communication device 352, and/or via other forms of vehicleto vehicle technology (V2V). The vehicles in the fleet 320 may alsocommunicate with the network cloud 360 via wireless communication 350.

Vehicle 310 may retrieve ambient (such as temperature, humidity etc.)and engine operating (such as catalyst temperature, speed) conditionsfrom one or more vehicles in the fleet 320. In one example, the fleet320 is within a threshold radius of the vehicle 310, the ambientconditions experienced by each of the vehicles in the fleet may besimilar to that experienced by the vehicle 310. The threshold radius maybe defined as a distance within which the ambient and consequentlyengine operating conditions may be considered to be similar to those ofvehicle 310. A statistical weighted average of the estimate retrievedfrom each vehicle of the remote fleet of vehicles and the estimateretrieved from the network cloud may be used by the control system 312of vehicle 310 to determine the future driving condition of the vehicle310. For example, when the average vehicle speed of fleet 320 is leverthan a threshold (5 mph, for example), and has continued to remain underthe threshold for a certain duration, it may be determined that thevehicle 310 may encounter slow moving traffic or stopped vehicles in thefuture. As such, the navigation system 354 may be able to deter nine thetraffic conditions, and estimate a time for which the condition maypersist. In this way the vehicle 310 may communicate with remote sources(external network cloud, other vehicles) using one or multipletechnologies e.g., wireless communication, navigation system and V2V.Various kinds of data (such as ambient temperature, humidity conditions,vehicle speed, traffic) may be exchanged among the vehicles and thenetwork cloud and this data may be utilized for enabling or delayingcatalyst heating actions as described in FIGS. 4-6.

The controller 12 of FIGS. 1 and 2, and the controller 314 of FIG. 3receive signals from the various sensors of FIGS. 1, 2 and 3 and employsthe various actuators of FIGS. 1, 2 and 3 to adjust engine operationbased on the received signals and instructions stored on a memory of thecontroller. Instructions for carrying out method 400 and the rest of themethods 500 and 600 included herein may be executed by a controllerbased on instructions stored on a memory of the controller and inconjunction with signals received from sensors of the engine system,such as the sensors described above with reference to FIGS. 1, 2 and 3.The controller may employ engine actuators of the engine system toadjust engine operation, according to the methods described below.

Turning now to FIG. 4, an example method 400 for delaying catalyticheating actions when the actions are determined to be unable to achievethreshold temperature within a threshold duration. Specifically, themethod predicts drive conditions wherein catalyst light-off temperaturesmay not be reached, and delays performing catalyst heating actionsduring such drive conditions.

Method 400 begins at 402 where vehicle operating conditions aredetermined and/or estimated. Operating conditions may include engineoperating conditions such as engine speed, engine load, intake air flowrate and/or pressure, throttle position, accelerator pedal position,ambient pressure, ambient temperature, speed, exhaust temperature, andthe like. The operating conditions further include load and/or state andtemperature of on one or more emission control devices such as three-waycatalyst, selective catalytic reduction (SCR) system, lean NOx trap,diesel particulate filter (DPF), oxidation catalyst, and the like.Herein, the catalyst refers to one or more catalysts and/or one or moreemission storage devices in the exhaust system of diesel, gasoline,hybrid vehicles and the like. The catalyst temperature may refer to theoperating or light-off temperature of the catalysts and the emissionstorage devices.

Method 400 then proceeds to 404 where a current driving condition isdetermined. For example, a current speed of the vehicle may bedetermined at 404. Determining the current driving conditions at 404 mayfurther include retrieving navigation data and/or drive history at 406.For example, a current location may be determined from navigation dataretrieved from the GPS. In addition, based on the current location andfurther based on a drive history, one or more of a destination and/orpreferred route may be determined. In some examples, the destinationinformation may be retrieved from an in-vehicle navigation system orfrom the navigation system of a blue tooth device. In some moreexamples, driver destination may be inferred from a statistical modelbased on drive history in conjunction with current drive parameters suchas vehicle speed, current location and the like.

Next, method 400 proceeds to 408, where a future driving condition ispredicted. The future driving condition may be predicted based oninformation retrieved from the cloud at 410 and further based oninformation relayed within the vehicle network at 412. As such, thecloud may share real-time traffic and road conditions data betweenvehicles connected in a vehicle-to-vehicle network. Informationretrieved from the cloud may include a preview of upcoming trafficconditions, type of roads, accidents along the route, stalled or stoppedvehicles, and the like. For example, when a long stretch of downwardsloping road is detected, it may indicate a coasting condition.Information relayed within the vehicle network may include one or moreof vehicle speed, an average speed of vehicles within the vehiclenetwork, duration for which the speed is maintained, and the like. Forexample, when the average speed of the vehicle is less than a threshold,the threshold being 5 mph, for example, a congestion in the traffic maybe deduced. In other examples, when higher average speeds are maintainedfor longer duration, it may indicate cruising conditions. In still otherexamples, when the average speed of the vehicles in the network is lowerfor longer period of time, then it may indicate an extended idlecondition.

Method 400 then proceeds to 414 where a duration may be estimated basedon communications external from the vehicle. As such, the duration mayindicate the time for which the drive condition persists, for example.In the example of the future driving condition including a trafficcongestion, the duration may include the time period for which thevehicle may experience the traffic congestion. Using real-time trafficdata, it may be possible to predict that duration for which the trafficcongestion may be present. In another example, if an average speed ofthe vehicles in the network increases, then again decreases wherein thespeed is maintained only for a short periods of time, then it mayindicate that there may be stop and go traffic up ahead, such asstart/stop condition. As such, the vehicle may be predicted to enter abusy stretch of road with lots of traffic lights. In such an example,the duration or the extent to which the start/stop condition may persistmay depend on the length of the road, the number of traffic stops, theduration for which a vehicle may stop at the traffic stop, trafficconditions along the stretch of road and the like.

As such, during certain driving conditions such as extended idle, forexample, the exhaust temperature may be expected to decrease. As anotherexample, during light load condition, when coasting in gear, little orno fuel may be used by the engine, and as such, exhaust temperatures maybegin to decrease. During such conditions, decreasing exhausttemperatures could indicate a decreasing catalyst temperature, forexample. Method 400 proceeds to 416 to determine if catalyst temperaturedrop is expected. Specifically, it may be determined if the catalysttemperature is expected to drop below a threshold, the threshold beingthe light-off temperature of the catalyst for example. During anextended idle condition, wherein the vehicle may be stopped altogetherfor extended periods of time, the catalyst temperature may slowly beginto decrease. Based on the duration estimated at 416, if the catalysttemperature drop is not expected to decrease below threshold during theestimated duration, then method proceeds to 418 where the engine may beoperated under nominal engine operation and the method ends. Herein, thecatalyst heating actions may not be adjusted, for example.

However, if a drop in catalyst temperature below the threshold isexpected when checked at 416, method 400 proceeds to 420 where it may bedetermined if catalyst heating actions may be able to achieve thresholdtemperature within the duration, the threshold being the light-offtemperature of the catalyst. As described earlier, diesel and gasolinevehicle exhaust systems may include one or more catalytic and/oremissions storage devices and each device may include an optimaltemperature (the light-off temperature) at which it may be optimallyoperated. When the temperature of the device or catalyst falls belowthreshold, various actions may be taken in the powertrain to deliverheat to the exhaust system including (but not limited to) delayingcombustion with injection or spark timing, changing exhaust gasrecirculation (EGR) rate, delaying transmission shift point, andincreasing engine load with accessory loads and the like.

If one or more of these actions may heat the device or catalyst tolight-off temperature within the estimated duration, then method 400proceeds to 422 where such heating actions may be enabled. However, ifsuch heating actions may not be able to heat the device or catalyst tothe light-off temperature within the duration, then method 400 proceedsto 424 where the catalyst heating action may be adjusted at 424.Adjusting catalyst heating action may further include stopping catalystheating actions at 426. In some examples, the catalyst heating actionmay be delayed for a certain time until one or more of the currentdriving condition and the future driving condition of the vehiclechanges. In this way, by anticipating drive condition wherein theheating actions may not result in exhaust being warmed up to operatingtemperature, intrusive heating actions to maintain or increase exhausttemperature may be avoided until a more suitable driving condition isencountered.

Thus, an example method includes adjusting catalyst heating actions inresponse to an expected decrease in temperature of a catalyst of avehicle below a threshold and an estimated duration thereof based oncommunications external from the vehicle, including delaying the actionsbased on the actions determined to be unable to achieve the thresholdwithin the duration, and enabling the actions based on the actionsdetermined to be able to achieve the threshold within the duration.Additionally, or alternatively, the method may further includeestimating the duration based on each of a current vehicle condition,and a future driving condition, the future driving condition determinedbased on the communications. Additionally, or alternatively, the methodmay further include determining the current vehicle condition based ondata retrieved from a navigational database of the vehicle and a drivinghistory. Additionally, or alternatively, the communications may includeinformation relayed within a vehicle network and information retrievedfrom a cloud. Additionally, or alternatively, the vehicle network mayinclude one or more vehicles travelling ahead of the vehicle and withina threshold distance from the vehicle. Additionally, or alternatively,the information may include one or more of the vehicle speed of thevehicle, and an average speed of vehicles within the vehicle network.Additionally, or alternatively, the information may further include oneor more of traffic data, the navigation data and the driving history.Additionally, or alternatively, the threshold may include catalystlight-off temperature.

In another representation, a method may include predicting an engineoutput profile over a horizon, and in response to catalyst temperatureless than a threshold, predict maximum engine temperature achievableover the engine output profile, and if the maximum engine temperature isless than light-off avoid modifying to increase exhaust temperature andmodify operation to accommodate no catalytic activity, and otherwise,perform catalyst heating operation. Additionally, or alternatively, themethod may further include predicting the maximum engine temperatureachievable based on a current driving condition, and a future drivingcondition of a target vehicle. Additionally, or alternatively, themethod may further include determining the current driving condition andthe future driving condition based on information relayed within avehicle network and retrieved from a cloud. Additionally, oralternatively the information may include one or more of a vehicle speedof a target vehicle, and an average speed of other vehicles within thevehicle network. Additionally, or alternatively, the information mayfurther include one or more of a traffic condition, a route and a drivehistory. Additionally, or alternatively performing catalyst heatingoperation may include performing one or more of exhaust warm-up actionsto increase the exhaust temperature, the warm-up actions includingdelaying combustion, changing exhaust gas recirculation rate, delayingtransmission shift point, and increasing engine load with accessoryload. Additionally, or alternatively, not performing the catalyticactivity may include not performing one or more of the exhaust warm-upaction until the predicted maximum engine temperature rises above thelight-off.

Turning now to FIG. 5, an example method 500 for avoiding catalystwarm-up actions during an extended idle condition is shown.Specifically, the method detects the extended idle condition based on acurrent vehicle speed and a predicted future driving condition, andfurther avoids performing catalyst warm-up actions during the extendedidle condition.

Method 500 begins at 502 where vehicle operating conditions aredetermined and/or estimated. Operating conditions may include engineoperating conditions such as engine speed, engine load, intake air flowrate and/or pressure, throttle position, accelerator pedal position,ambient pressure, ambient temperature, vehicle speed, exhausttemperature, and the like. The operating conditions further include loadand/or state and temperature of on one or more emission control devicessuch as three-way catalyst, selective catalytic reduction (SCR) system,lean NOx trap, diesel particulate filter (DPF), oxidation catalyst, andthe like.

Next at 504, method 500 determines if the vehicle speed is droppingbelow a threshold speed Thr_VS. The vehicle speed may be determined fromthe output of speed sensors in the vehicle, for example. In someexamples, deceleration or rate of decrease of vehicle speed may bechecked at 504. If the vehicle speed is above the threshold Thr_VS, thenmethod ends.

However, if the vehicle speed is lower than the threshold, then method500 proceeds to 506 where a future driving condition may be predicted.As such, future driving condition may be predicted by first determininga current driving condition at 508. The current driving condition mayinclude a current location of the vehicle for example. The currentlocation may be determined from data received from GPS, for example.Additionally and/or alternatively, the current driving condition mayinclude determining a current catalyst temperature. As such, the currentcatalyst temperature may be determined from the output of one or moretemperature sensors of the catalyst. In some examples, the currentcatalyst temperature may be deduced from the exhaust gas temperature.Herein, the catalyst refers to one or more catalysts and also one ormore emission storage devices in the exhaust system of diesel, gasoline,hybrid vehicles and the like.

Next, at 510, method 500 includes receiving data from cloud. As such,the cloud may share real-time traffic and road conditions data betweenvehicles connected in a vehicle-to-vehicle network. Herein, the clouddata may include an average vehicle speed of vehicles within the vehiclenetwork. Further, at 512, navigation data may be retrieved. As such, thenavigation data may include a destination deduced based on drivehistory, for example. Navigation data may additionally and/oralternatively include a preferred route, further deduced from the drivehistory. As such, the future driving condition may be predicted based onthe current driving condition, cloud data and navigation data, all ofwhich may be received concurrently or sequentially. When the averagevehicle speed of the vehicles in the network is below a threshold speedfor a certain duration of time, the future driving condition may bepredicated to be an extended idle condition.

As such, based on a current location and navigation data, a preferreddestination and/or route may be determined. Further, the traffic datareceived from the cloud may show stopped vehicles due to an accident orconstruction up ahead.

Next at 514, method 500 includes predicting time t1 when the vehiclespeed will rise above threshold Thr_VS. Said another way, the time t1may be the time at which the extended idle condition may be predicted toend. As such, based on the communications within the V2V network, it maybe possible to determine when the extended idle condition may end, forexample. For example, by communicating with the V2V network, it may beable to predict when the extended idle condition may end, for example,and further determine when the vehicle speed may begin to increase in acertain time, say t1.

Then, method 500 proceeds to 516, where a time t2, at which the catalysttemperature will fall below the threshold Thr (Thr being the light-offtemperature of the catalyst) may be predicted. As such, when the vehicleis in extended idle condition, the catalyst temperature may begin todecrease. Herein, a rate at which the catalyst temperature is decreasingmay be estimated. Knowing the catalyst light-off temperature, based onthe estimated rate of decrease, the time t2 at which the catalysttemperature will fall below the light-off temperature may be predicted.

Method 500 then proceeds to 518, where it may be checked if thepredicted time, t1 when vehicle speed will rise above threshold isgreater than the predicted time, t2 when the catalyst temperature willfall below Thr. If time t1 is greater than t2, indicating that thecatalyst temperature will fall below threshold while the vehicle isstill in extended idle condition, then method 500 proceeds to 522 wherecatalyst warm-up actions may be avoided. As such, when catalyst warm-upactions are performed while the vehicle is in extended idle, the warm-upactions may not be able to increase the catalyst to light-offtemperatures, for example. Thus, during such extended idle condition,catalyst warm-up actions may be avoided. However, if time t1 is lesserthan time t2, indicating that the extended idle will end before thecatalyst temperature falls below the light-off temperature, method 500proceeds to 520 wherein the catalyst warm-up actions may be performedbased on the catalyst temperature. Herein, the catalyst warm-up actionsmay be able to achieve the light-off temperature and hence the catalystwarm-up actions may be performed and then the method ends.

Retuning to 522, where the catalyst warm-up actions are avoided, themethod may proceed to 524 to determine if the vehicle speed is risingabove the threshold. As such, if the vehicle speed rises above thethreshold, it may indicate that the extended idle condition has ended.If the extended idle condition has ended, then method proceeds to 528where the catalyst warm-up actions may be performed, otherwise, method500 proceeds to 526 where the catalyst warm-up actions may be continuedto be delayed. In this way, the method may continuously monitor thedriving conditions and delay performing the catalyst warm-up actionsuntil more favorable conditions are encountered.

Turning to FIG. 7, plot 700 shows an example relationship betweenvehicle speed and catalyst temperature. The curve 702 of FIG. 7 showsthe vehicle speed and the curve 704 shows the catalyst temperatureduring different driving conditions. Horizontal dashed line 710corresponds to a threshold vehicle speed and horizontal dashed line 712corresponds to threshold catalyst temperature. The X axis representstime and time increases from the left to the right side of the plot. TheY axis of the top plot represents vehicle speed and is the lowest at thebottom of the graph and increases in magnitude towards the top of theplot. Likewise, the Y axis of the bottom plot represents temperature andis the lowest at the bottom of the graph and increases in magnitudetowards the top of the plot.

At time t0, the vehicle speed (702) is above the threshold speed (710),and the catalyst temperature (704) is higher than threshold temperature(712). The threshold temperature may be a light-off temperature of thecatalyst. Since the catalyst temperature is higher than the light-offtemperature, catalyst heating operations may not be initiated.

The time between t1 and t5 represents a first driving condition. Betweentime t1 and t2, there is a drop in vehicle speed (702), and during thistime interval, the vehicle speed drops below the threshold (710). Attime t1, when the vehicle speed begins to drop below the thresholdspeed, a future time t′4 at which the vehicle speed will rise abovethreshold 710 may be predicted. As explained earlier, the predicted timet′4 may be estimated based on a predicted future driving condition. Assuch, the future driving condition may be predicted based on one or moreof a current driving condition, navigation data, cloud data and drivehistory. Further, based on a rate of decrease of vehicle speed and arate of decrease of exhaust temperature, a time t2 at which the catalysttemperature will fall below the threshold 712 may be predicted. As such,first predicted time period or duration T1 for the vehicle speed to riseagain threshold may be equal to (t′4−t1) and the second predicted timeperiod or duration T2 for the catalyst temperature to fall belowthreshold temperature may be equal to (t2−t1).

As one example, when the vehicle speed of a target vehicle falls belowthreshold at time t1, a current location of the target vehicle may bedetermined. The current location may be determined based on a signalfrom the GPS. Further, a future driving condition may be predicted.Based on the navigation data and/or drive history, a preferred route maybe determined. Along the preferred route, a V2V communication may beestablished with a threshold number of vehicles within a thresholddistance from the target vehicle, for example. For example, an averagespeed of vehicles in the vehicle network may be received from the cloud.Based on the average vehicle speed being lower than a threshold, it maybe determined that the vehicles in the vehicle network may be stoppedahead. Then, real-time traffic data may be received from the cloud. Forexample, the traffic data may indicate the due to an accident along theroute, there are stopped vehicles ahead. Based on the real-time trafficupdates, the time at which the vehicles in the network will start movingwill be estimated, and further, the time duration T1 at which the targetvehicle's speed will rise above threshold may be predicted. If T1 islonger than a threshold, then it may be determined that the vehicle isin extended idle condition, for example.

When the target vehicle is in extended idle condition, the exhausttemperatures may start to decrease and further the catalyst temperaturemay also begin to decrease. Based on a rate of decrease of the catalysttemperature (given by slope of curve 704), it may be predicted that thecatalyst temperature will fall below the threshold at time t2. Further,the time duration T2 at which the catalyst temperature will fall belowthe threshold 712 may be predicted. Herein, the threshold may includethe light-off temperature of the catalyst and T2 may be equal to(t2−t1).

As such, when the catalyst temperature falls below the threshold,catalyst warm-up or heating actions may be recommended at t3. The dashedcurve 706 shows the predicted increase in catalyst temperature if therecommended catalyst heating actions are performed. However, since T1 isgreater than T2, the heating actions will not be initiated at time t3 asrecommended. This is because, during the extended idle condition,catalyst heating actions may not allow enough heat to get to the exhaustsystem to light-off the active exhaust components even with theintrusive powertrain heating actions. As such, any action taken to warmthe exhaust is wasted because it may not yield the desired emissionsreduction implying that fuel economy is reduced and the driver may benegatively impacted for no net benefit. Thus, the catalyst heatingactions may be avoided at t3, and the catalyst temperature may beallowed to drop (704).

At time t4, the target vehicle speed starts to rise (plot 702). Forexample, the accident may have cleared up, and as a result the vehiclesalong the route may begin to move. At time t4, if the catalyst heatingactions are initiated, the catalyst temperature may begin to increase(as shown by dashed curve 708). However, based on cloud data andnavigation data, it may be determined that the target vehicle has ashort drive ahead, after which another extended idle condition may occurat time t5. For example, the navigation data may indicate that thedestination of the target vehicle will arrive within a short distance,at time t5. In another example, the real-time traffic data and V2Vcommunication may further predict another extended idle starting at timet5. In both examples of a short drive to the destination or anotherpredicted extended idle condition, catalyst heating action initiated attime t4 will not be able to heat up the catalyst to the thresholdtemperature. This is shown by dashed curve 708, wherein the catalysttemperature fails to reach the threshold before the time t5, and hencethe catalyst warm-up actions may be further delayed until more favorabledrive conditions are predicted.

In this way, based on communication with the cloud and further tovehicles in a network of vehicles, it may be possible to adjust catalystheating actions, and only perform the actions when there is possibilityof the catalyst to reach up to light-off temperatures within the drivecycle, for example.

Another example drive condition is shown between time t6 and t7. At timet7, there is a drop in vehicle speed (702), and during this timeinterval, the vehicle speed drops below the threshold (710). At time t7,when the vehicle speed begins to drop below the threshold speed, afuture time t′9 at which the vehicle speed will rise above threshold 710may be predicted. As explained earlier, the predicted time t′9 may beestimated based on a predicted future driving condition. As such, thefuture driving condition may be predicted based on one or more of acurrent driving condition, navigation data, cloud data and drivehistory. Further, based on a rate of decrease of vehicle speed and arate of decrease of exhaust temperature, a time t8 at which the catalysttemperature will fall below the threshold 712 may be predicted. As such,first predicted time period or duration T1 for the vehicle speed to riseagain threshold may be equal to (t′9−t7) and the second predicted timeperiod or duration T2 for the catalyst temperature to fall belowthreshold temperature may be equal to (t7−t6).

When the vehicle speed of a target vehicle falls below threshold at timet7, a current location of the target vehicle may be determined. Thecurrent location may be determined based on a signal from the GPS.Further, a future driving condition may be predicted. Based on thenavigation data and/or drive history, a preferred route may bedetermined. Along the preferred route, a V2V communication may beestablished with a threshold number of vehicles within a thresholddistance from the target vehicle, for example. For example, an averagespeed of vehicles in the vehicle network may be received from the cloud.Based on the average vehicle speed being lower than a threshold, it maybe determined that the vehicles in the vehicle network may be stoppedahead. Then, real-time traffic data may be received from the cloud. Forexample, the traffic data may indicate the due to a construction alongthe route, there is slow moving traffic ahead. Based on the real-timetraffic updates, the time at which the vehicles in the network willstart moving at threshold speeds will be estimated, and further, thetime duration T1 at which the target vehicle's speed will rise abovethreshold may be predicted. However, T1 may be lower than the threshold,and it may be determined that the vehicle is not in extended idlecondition, but going through slow moving traffic, for example.

When the target vehicle is in stop and go, slow moving traffic, theexhaust temperatures may start to decrease and further the catalysttemperature may also begin to decrease. Based on a rate of decrease ofthe catalyst temperature (given by slope of curve 704), it may bepredicted that the catalyst temperature will fall below the threshold attime t7. Further, the time duration T2 (t7−t6) at which the catalysttemperature will fall below the threshold 712 may be predicted. Herein,the threshold may include the light-off temperature of the catalyst.

As such, when the catalyst temperature falls below the threshold,catalyst warm-up or heating actions may be recommended at t8. In someexample, the catalyst heating actions may be recommended at t7. Thedashed curve 714 shows the predicted increase in catalyst temperature ifthe recommended catalyst heating actions are performed. Though T1 isgreater than T2, but T1 is however lower than the threshold that maycorresponds to extended idle condition, say, the heating actions may beinitiated at time t8 as recommended. This is because, during the slowmoving condition, catalyst heating actions may allow enough heat to getto the exhaust system to light-off the active exhaust components. Assuch, the heating action taken to warm the exhaust is not wasted becauseit will yield the desired emissions reduction. Thus, the catalystheating actions may be performed at t8, and the catalyst temperature maybe allowed to increase (714).

Based on cloud data and navigation data, it may be determined that thespeed of the target vehicle will increase above threshold at t′9. Forexample, the navigation data may indicate that an end of constructionzone, and speeds of the vehicles in the vehicle network increasing abovethreshold. Thus, initiating the catalyst heating actions at t8, willallow the catalyst to warm-up to catalyst light-off temperature at t9,for example.

In this way, based on communication with the cloud and further tovehicles in a network of vehicles, it may be possible to adjust catalystheating actions, and only perform the actions when there is possibilityof the catalyst to reach up to light-off temperatures within the drivecycle, for example.

Another example drive condition is shown between time t11 and t14. Attime t11, there is a drop in vehicle speed (702), and the vehicle speeddrops below the threshold (710) at time t12. At time t11, when thevehicle speed begins to drop below the threshold speed, a future timet′12 at which the vehicle speed will rise above threshold 710 may bepredicted. As explained earlier, the predicted time t′12 may beestimated based on a predicted future driving condition. As describedearlier, the future driving condition may be predicted based on one ormore of a current driving condition, navigation data, cloud data anddrive history. Further, based on a rate of decrease of vehicle speed anda rate of decrease of exhaust temperature, a time t12 at which thecatalyst temperature will fall below the threshold 712 may be predicted.As such, first predicted time period or duration T1 for the vehiclespeed to rise again threshold may be equal to (t′12−t12) and the secondpredicted time period or duration T2 for the catalyst temperature tofall below threshold temperature may be equal to (t13−t12).

When the vehicle speed of a target vehicle falls below threshold at timet12, a current location of the target vehicle may be determined. Thecurrent location may be determined based on a signal from the GPS.Further, a future driving condition may be predicted. Based on thenavigation data and/or drive history, a preferred route may bedetermined. Along the preferred route, a V2V communication may beestablished with a threshold number of vehicles within a thresholddistance from the target vehicle, for example. For example, an averagespeed of vehicles in the vehicle network may be received from the cloud.Based on the average vehicle speed being lower than a threshold, it maybe determined that the vehicles in the vehicle network may be travellingat lower speeds, which may be predicted to last only for a shortduration, based on real-time traffic data, for example. Based on thereal-time traffic updates, the time at which the vehicles in the networkwill start moving at threshold speeds will be estimated, and further,the time duration T1 at which the target vehicle's speed will rise abovethreshold may be predicted. However, T1 may be lower than the thresholdduration for extended idle condition for example, and it may bedetermined that the vehicle is not in extended idle condition, but goingthrough slow moving traffic.

When the target vehicle is in stop and go, slow moving traffic, theexhaust temperatures may start to decrease and further the catalysttemperature may also begin to decrease. Based on a rate of decrease ofthe catalyst temperature (given by slope of curve 704), it may bepredicted that the catalyst temperature will fall below the threshold attime t12. Further, the time duration T2 (t13−t12) at which the catalysttemperature will fall below the threshold 712 may be predicted. Herein,the threshold may include the light-off temperature of the catalyst.

As such, when the catalyst temperature falls below the threshold,catalyst warm-up or heating actions may be recommended at t8. In someexample, the catalyst heating actions may be recommended at t7. Since T2is longer than T1, catalyst actions may be performed. Thus, the catalystheating actions may be performed at t′12, and the catalyst temperaturemay be allowed to increase (704).

In this way, based on communication with the cloud and further tovehicles in a network of vehicles, it may be possible to adjust catalystheating actions, and perform the actions when there is possibility ofthe catalyst to reach up to light-off temperatures within the drivecycle, for example.

Thus, an example method for a vehicle, includes in response to a vehiclespeed dropping below a threshold speed, avoiding exhaust warm-up actionswhen a first predicted time for the vehicle speed to rise above thethreshold speed is longer than one or more of a second estimated timefor a catalyst temperature to fall below a threshold temperature and athreshold duration, and performing the exhaust warm-up actions when thefirst time is shorter than the second time. Additionally, oralternatively, the method may further include determining the firstpredicted time based on a current driving condition and a predictedfuture driving condition. Additionally, or alternatively, the method mayinclude determining the current driving condition and the predictedfuture driving condition based on data retrieved from a cloud.Additionally, or alternatively, the method may include determining thefirst predicted time based on one or more of navigation data and trafficdata. Additionally, or alternatively, the threshold temperature mayinclude a light-off temperature of a catalyst and the threshold durationmay include an extent of an extended idle drive condition.

Turning now to FIG. 6, an example method 600 for starting catalystheating based on destination input received from a driver of the hybridelectric vehicle and a predicted start/stop of the vehicle is shown.Specifically, method 600 includes starting catalyst heating when thepredicted start/stop is below a threshold number, and not starting thecatalyst heating otherwise.

Method 600 begins at 602 where it is determined if a driver destinationis received. In some examples, receiving drive destination may include adriver entering a destination in a GPS, for example. In some otherexamples, the driver destination may be inferred based on drive history.If driver destination is not received, then method ends.

If driver destination is received at 602, then method proceeds to 604,where a number of start/stop cycles of the vehicle may be predicted. Inhybrid electric vehicles, during start-stop cycle of the vehicle, theengine may be automatically shut-down and be restarted to reduce theamount of time the engine spends idling, thereby reducing fuelconsumption and emissions. Predicting the number of start/stop cycles ofthe vehicle may be based on a current driving condition estimated at 606and further based on a future driving condition predicted at 608. Assuch, estimating a current driving condition includes estimating one ormore of a current vehicle location, a current speed, and the like.Predicting the future driving condition may further include receivingnavigation and cloud data at 614, and predicting the future drivingcondition based on the received data. For example, the navigation datamay include a route generated based on the destination input received at602. Data received from the cloud may include real-time traffic and roadconditions and further include data (such as average vehicle speed ofvehicles in the network) transceived between vehicles connected in avehicle-to-vehicle network. Herein, the data retrieved from the cloudmay include a preview of upcoming traffic conditions, types of roads,accidents along the route, stalled or stopped vehicles, number oftraffic lights, and the like.

Next, method proceeds to 618 where it is determined if the predictednumber of start/stop cycles of the vehicle is higher than a thresholdnumber. If “YES”, then method 600 proceeds to 624 where the catalystheating may not be started when the catalyst temperature is belowlight-off, for example. Herein, not starting the catalyst heating mayinclude not starting the engine on restart at 626 and the method ends.

However, if the predicted number of start/stop cycles of the vehicle islower than the threshold, then method 600 proceeds to 620 where thecatalyst heating may be started when the catalyst temperature fallsbelow light-off, for example. Herein, starting the catalyst heating mayinclude starting the engine on restart at 626, and the method ends.

For example, controller 12 may identify and/or control the amount ofelectrical energy stored at the energy storage device, which may bereferred to as the state of charge (SOC). Turning to FIG. 8, plot 800shows an example relationship between a state of charge (SOC) of anenergy storage device in a hybrid electric vehicle, combustion engine inthe hybrid electric vehicle and a catalyst temperature. The curve 802 ofFIG. 8 shows the SOC, the curve 804 shows the engine turning ON and OFF,and the curve 806 shows the catalyst temperature of the catalyst in theexhaust system of the engine. Horizontal dashed line 808 corresponds toa threshold charge and horizontal dashed line 810 corresponds tothreshold catalyst temperature. The X axis represents time and timeincreases from the left to the right side of the plot. The Y axis of thetop plot represents amount of charge and is the lowest at the bottom ofthe graph and increases in magnitude towards the top of the plot.Likewise, the Y axis of the bottom plot represents temperature and isthe lowest at the bottom of the graph and increases in magnitude towardsthe top of the plot.

At time t0, the engine of the HEV may be OFF (804) and the catalysttemperature (806) may be higher than a threshold (810), for example.Herein, the HEV may be operated in charge depleting mode. During thecharge depleting mode the HEV operation may be dependent on energy orSOC of the battery pack. As an example, the HEV may operate in chargedepleting mode at startup, and switch to charge-sustaining mode afterthe battery has reached its minimum SOC threshold.

At time t1, a destination input may be received from a driver of theHEV, for example. As explained earlier, receiving destination input mayinclude the driver entering a destination in a GPS, for example. In someexamples, the destination may be inferred based on drive history.

Based on the destination received at time t1, a number of start/stop maybe predicted. Thus, between t1 and t2, the number of start/stop may bepredicted. However, to predict the number of start stop, a currentdriving condition may be determined. The current driving condition mayinclude a current location of the vehicle as determined based on signalfrom a GPS, for example. Further, based on the destination a futuredriving condition may be predicted. Predicating the future drivingcondition may include generating a preferred route. Within the preferredroute, a network of vehicles may be selected and external communicationmay be established between the vehicles in the network and a cloud. Forexample, the network may include a fleet of vehicles at a thresholddistance ahead of the target vehicle, for example. Furthermore,real-time traffic and road conditions may be retrieved from the cloud.Based on each of the current driving condition and the future drivingconditions, the number of start/stop of the vehicle may be predicted.

In an example scenario, at t1, it may be determined that the vehicle isin a busy stretch of road with greater than threshold number of trafficlights. Further, based on the time of the day, it may be determined thatthe traffic lights may stay on for longer times. Thus, it may bepredicted that the vehicle may encounter greater than threshold numberof start/stops between time t1 and t2.

At time t1, the catalyst temperature (806) is below threshold (810). Inone example, the threshold may include the light-off temperature of thecatalyst. However, catalyst warm-up actions may be delayed, since thepredicted number of start/stop is greater than the threshold number.Additionally, since the SOC is higher than the threshold charge (808),the engine may be continued to be OFF between t1 and t2. Thus, thecatalyst temperature will be allowed to fall below threshold and theengine may not be turned ON to heat up the catalyst to light-offtemperatures.

Another example drive condition is shown between t3 and t7. At time t3,a destination input may be received from a driver of the HEV, forexample. As explained earlier, receiving destination input may includethe driver entering a destination in a GPS, for example. In someexamples, the destination may be inferred based on drive history.

Further, a current driving condition and a future driving condition maybe determined at time t1. The future driving condition, as determined byestablishing communications with a network of vehicles and a cloud, maypredict a steep uphill for a long duration between time t4 and t6. Att4, the catalyst temperature falls below threshold temperature. However,between t4 and t5, the SOC (802) is higher than the threshold charge(808), and hence the engine may be continued to be OFF between t4 andt5, and the catalyst temperature may be allowed to decrease.

At time t5, the SOC may reach threshold charge. If the engine is notturned ON, then the SOC may continue to drop as shown by dashed curve812. In order to avoid the SOC falling below the threshold, the enginemay be turned ON at t5, and continued to be ON for the time between t5and t7. Herein, turning ON the engine will increase the catalysttemperature, and the catalyst temperature may rise above threshold. Theengine may be turned OFF at t7, when both the SOC is above thresholdcharge and the catalyst temperature is above light-off, for example.

Thus, an example method for a hybrid vehicle, includes in response toreceiving a destination, predicting a number of start-stop cycle in aroute of the vehicle, not starting engine on restart when catalysttemperature is below light-off when the number of start-stop cycle ishigher than a threshold number, and starting the engine on restart whencatalyst temperature is below light-off when the number of start-stopcycle is lower than the threshold number. Additionally, oralternatively, the method may further include predicting a durationbetween the start-stop cycle of the vehicle, and not starting the engineon restart when catalyst temperature is below light-off when theduration is lower than a threshold duration. Additionally, oralternatively, the method may further include starting the engine onrestart when catalyst temperature is below light-off when the durationis higher than the threshold duration. Additionally, or alternatively,the method may further include predicting the duration between astart-stop cycle of the vehicle and the number of start-stop cycle basedon a current location of the vehicle, and navigation data and furtherbased on cloud data from a vehicle to vehicle network. Additionally, oralternatively, the method may further include adjusting the starting ofthe engine based on a state of charge of a battery of the vehicle.Additionally, or alternatively, the start-stop cycle may include asingle vehicle-on, and engine-run and a vehicle-off with lower thanthreshold engine-run.

In this way, by anticipating drive conditions wherein the exhaust maynot be warmed up to operating temperature, intrusive exhaust warm-upactions may be delayed or stopped until a more favorable driveconditions occur. Thus, driver experience may be enhanced and furthercost of heating may be reduced. The technical effect of delaying theexhaust warm-up actions based on the predicated drive conditions, isthat an optimal strategy may be devised that continuously monitors fuelcost of heating and the impact to the driver versus delaying catalystheating until more favorable conditions exist.

The systems and methods described above also provide for a method, themethod comprising adjusting catalyst heating actions in response to anexpected decrease in temperature of a catalyst of a vehicle below athreshold and an estimated duration thereof based on communicationsexternal from the vehicle, including: delaying the actions based on theactions determined to be unable to achieve the threshold within theduration, and enabling the actions based on the actions determined to beable to achieve the threshold within the duration. In a first example ofthe method, the method may additionally or alternatively includeestimating the duration based on each of a current vehicle condition,and a future driving condition, the future driving condition determinedbased on the communications. A second example of the method optionallyincludes the first example, and further includes determining the currentvehicle condition based on data retrieved from a navigational databaseof the vehicle and a driving history. A third example of the methodoptionally includes one or more of the first and the second examples,and further includes wherein the communications include informationrelayed within a vehicle network and information retrieved from a cloud.A fourth example of the method optionally includes one or more of thefirst through the third examples, and further includes wherein vehiclenetwork includes one or more vehicles travelling ahead of the vehicleand within a threshold distance from the vehicle. A fifth example of themethod optionally includes one or more of the first through the fourthexamples, and further includes wherein the information includes one ormore of the vehicle speed of the vehicle, and an average speed ofvehicles within the vehicle network. A sixth example of the methodoptionally includes one or more of the first through the fifth examples,and further includes wherein the information further includes one ormore of traffic data, the navigation data and the driving history. Aseventh example of the method optionally includes one or more of thefirst through the sixth examples, and further includes wherein thethreshold includes catalyst light-off temperature.

The systems and methods described above also provide for a method, themethod comprising in response to a vehicle speed dropping below athreshold speed, avoiding exhaust warm-up actions when a first predictedtime for the vehicle speed to rise above the threshold speed is longerthan one or more of a second estimated time for a catalyst temperatureto fall below a threshold temperature and a threshold duration, andperforming the exhaust warm-up actions when the first time is shorterthan the second time. In a first example of the method, the method mayadditionally or alternatively includes determining the first predictedtime based on a current driving condition and a predicted future drivingcondition. A second example of the method optionally includes the firstexample, and further includes determining the current driving conditionand the predicted future driving condition based on data retrieved froma cloud. A third example of the method optionally includes one or moreof the first and the second examples, and further includes whereindetermining the first predicted time based on one or more of navigationdata and traffic data. A fourth example of the method optionallyincludes one or more of the first through the third examples, andfurther includes wherein the threshold temperature includes a light-offtemperature of a catalyst. A fifth example of the method optionallyincludes one or more of the first through the fourth examples, andfurther includes wherein the threshold duration includes an extent of anextended idle drive condition.

The systems and methods described above also provide for a system for ahybrid vehicle, the system comprising an engine coupled to an exhaustaftertreatment, an energy storage device configured to store energy, anda controller comprising a computer readable storage medium comprisinginstructions that are executed to in response to receiving adestination, predicting a number of start-stop cycle in a route of thevehicle, not starting engine on restart when catalyst temperature isbelow light-off when the number of start-stop cycle is higher than athreshold number, and starting the engine on restart when catalysttemperature is below light-off when the number of start-stop cycle islower than the threshold number. In a first example of the system, thesystem may additionally or alternatively include a navigation system incommunication to a network of vehicles and a cloud and wherein theinstructions are further executed to predict a duration between thestart-stop cycle of the vehicle based on data received from thenavigation system, and not starting the engine on restart when catalysttemperature is below light-off when the duration is lower than athreshold duration. A second example of the system optionally includesthe first example and further wherein the instructions are furtherexecuted to start the engine on restart when catalyst temperature isbelow light-off when the duration is higher than the threshold duration.A third example of the system optionally includes one or more of thefirst and the second examples, and further includes wherein theinstructions are further executed to predict the duration between astart-stop cycle of the vehicle and the number of start-stop cycle basedon a current location of the vehicle, and navigation data and furtherbased on cloud data from the network of vehicles. A fourth example ofthe system optionally includes one or more of the first through thethird examples, and further includes wherein the instructions arefurther executed to adjust the starting of the engine based on a stateof charge of the energy storage device of the vehicle. A fifth exampleof the system optionally includes one or more of the first through thefourth examples, and further includes wherein the start-stop cycleincludes a single vehicle-on, and engine-run and a vehicle-off withlower than threshold engine-run.

Note that the example control and estimation routines included hereincan be used with various engine and/or vehicle system configurations.The control methods and routines disclosed herein may be stored asexecutable instructions in non-transitory memory and may be carried outby the control system including the controller in combination with thevarious sensors, actuators, and other engine hardware. The specificroutines described herein may represent one or more of any number ofprocessing strategies such as event-driven, interrupt-driven,multi-tasking, multi-threading, and the like. As such, various actions,operations, and/or functions illustrated may be performed in thesequence illustrated, in parallel, or in some cases omitted. Likewise,the order of processing is not necessarily required to achieve thefeatures and advantages of the example embodiments described herein, butis provided for ease of illustration and description. One or more of theillustrated actions, operations and/or functions may be repeatedlyperformed depending on the particular strategy being used. Further, thedescribed actions, operations and/or functions may graphically representcode to be programmed into non-transitory memory of the computerreadable storage medium in the engine control system, where thedescribed actions are carried out by executing the instructions in asystem including the various engine hardware components in combinationwith the electronic controller.

It will be appreciated that the configurations and routines disclosedherein are exemplary in nature, and that these specific embodiments arenot to be considered in a limiting sense, because numerous variationsare possible. For example, the above technology can be applied to V-6,1-4, 1-6, V-12, opposed 4, and other engine types. The subject matter ofthe present disclosure includes all novel and non-obvious combinationsand sub-combinations of the various systems and configurations, andother features, functions, and/or properties disclosed herein.

The following claims particularly point out certain combinations andsub-combinations regarded as novel and non-obvious. These claims mayrefer to “an” element or “a first” element or the equivalent thereof.Such claims should be understood to include incorporation of one or moresuch elements, neither requiring nor excluding two or more suchelements. Other combinations and sub-combinations of the disclosedfeatures, functions, elements, and/or properties may be claimed throughamendment of the present claims or through presentation of new claims inthis or a related application. Such claims, whether broader, narrower,equal, or different in scope to the original claims, also are regardedas included within the subject matter of the present disclosure.

1-14. (canceled)
 15. A system for a hybrid vehicle, comprising: anengine coupled to an exhaust aftertreatment; an energy storage deviceconfigured to store energy; and a controller comprising a computerreadable storage medium comprising instructions that are executed to: inresponse to receiving a destination, predicting a number of start-stopcycles in a route of the vehicle; not starting the engine on restartwhen catalyst temperature is below light-off when the number ofstart-stop cycles is higher than a threshold number; and starting theengine on restart when the catalyst temperature is below light-off whenthe number of start-stop cycles is lower than the threshold number. 16.The system of claim 15, further comprising a navigation system incommunication with a network of vehicles and a cloud and wherein theinstructions are further executed to predict a duration betweenstart-stop cycles of the vehicle based on data received from thenavigation system, and not starting the engine on restart when thecatalyst temperature is below light-off when the duration is lower thana threshold duration.
 17. The system of claim 16, wherein theinstructions are further executed to start the engine on restart whenthe catalyst temperature is below light-off when the duration is higherthan the threshold duration.
 18. The system of claim 16, wherein theinstructions are further executed to predict the duration betweenstart-stop cycles of the vehicle and the number of start-stop cyclesbased on a current location of the vehicle, and navigation data andfurther based on cloud data from the network of vehicles.
 19. The systemof claim 15, wherein the instructions are further executed to adjust thestarting of the engine based on a state of charge of the energy storagedevice of the vehicle.
 20. The system of claim 16, wherein a start-stopcycle includes a single vehicle-on, and engine-run and a vehicle-offwith lower than threshold engine-run.